1. Field of the Invention
The present invention relates to a drinking straw which delivers a hot liquid into the mouth of a user in the form of a foam and to a method wherein the hot liquid is cooled in the user's mouth as the foam collapses such that the mouth of the user is not burned. The drinking straw may be provided separately or in combination with a drinking vessel.
2. Brief Description of the Prior Art
To reduce the chance of burning the mouth, people instinctively sip a hot liquid. The sipping process mixes the hot liquid with air, thus creating an air-liquid mixture. The air keeps the liquid from burning the user's mouth while the liquid cools.
Other than with the natural technique, inventive attention has been directed to cooling the hot liquid before it reaches the user's mouth. But a cooled drink and a hot drink have different flavors. U.S. Pat. No. 5,288,019 to Gorochow is illustrative of the prior art.
The idea of perforating a straw such it introduces bubbles into a drink for the purpose of improving the drink's palatability was described in U.S. Pat. No. 2,943,794 to Sussman. The tube wall in the Sussman patent is straight and the bubbles introduced into the drink tend to be small. When such a straw is used with a hot liquid, the liquid is slightly cooled as it flows through the straw but it is still hot when it reaches a user's mouth and the bubbles are not large enough to effectively form a foam.
In view of the above, what is needed is a drinking straw and a method of cooling a hot liquid that mimics the natural action of sucking in air for cooling the liquid.